Generally speaking, the present invention refers to an on-site articulated imbrication process between concrete slabs. More specifically, the invention refers to a joint formation process in on-site linear works and concrete paving like roads, streets, motorways, railways, channels and port and airport platforms together with the means for their execution.
Amongst the devices known in the art for forming joints in concrete pavings, the following can be cited
1) The distribution blocks described in Spanish Patent 438.002.
2) The classic plastic coated steel pins located towards the middle of the slab thickness such as, for example, those described in U.S. Pat. No. 3,437,017, have the drawback of creating strong, localized pressure resulting in a clearance of the space they occupy in the concrete, hence reducing their effectiveness. For this reason, either large slab thicknesses are necessary or lower base and sub-base layers. Moreover, the insertion of lateral pins has not yet given a satisfactory result.
3. The undulated plates, vertically arranged on the ground and fastened to it, require lateral feeding, reducing works yield and making another lateral access necessary. This solution has not given the expected result since the intended formation of teeth is not achieved and hence, load transmission is not obtained.
4. My Spanish applications P-9402515 xe2x80x9cCoplanar Coupling System Between Concrete Slabsxe2x80x9d filed on Dec. 9th 1994, and P-9500530, xe2x80x9cJoint System Between Concrete and Similar Slabsxe2x80x9d, filed on Mar. 9th 1995, and my application PCT/ES95/00072, xe2x80x9cConstruction Process for Linear Concrete Works With Internal Gaps and Execution Devicesxe2x80x9d; filed on Jun. 9th 1995. These systems require the load on the edges of adjacent slabs immediately after completing the superficial groove and before the concrete begins to shrink which sometimes causes more cracks than desirable, provoking the insecurity of these systems. The process described herein is produced in a fully natural or automatic way and therefore is safe.
By means of a device, the described process, takes advantage of the concrete shrinking with the object of leaving the edges of the resulting slabs leaning over each other. It is complemented with a separating component preventing the arrival of water to the platform across these edges and may be fastened to the mentioned device.
The device is a corrugated steel mesh installed with its axis parallel and contained in the axis plane of the joint to be obtained. Cuts are made and several wires are bent, perpendicular to the mesh axis, towards the side where cuts have not been made, forming an angle. The wires existing outside are cut from the other side of the mesh axis and are bent in the opposite direction to the previous ones. Continuing in this manner, we obtain iron pieces alternatively inclined to one side or the other of the mesh axis, which will form part of the inclined support surfaces of a slab over the adjacent one. This mesh shape loads the cracks created through the upwards part downwards and the same is done for the cracks created from downwards upwards, forming a single crack.